Calcium

From the Latin word
calx
, lime. Though lime was prepared by the Romans in the first century under the name calx, the metal was not discovered until 1808. After learning that Berzelius and Pontin prepared calcium amalgam by electrolyzing lime in mercury, Davy was able to isolate the impure metal.

Calcium, a metallic element, is fifth in abundance in the earth's crust, of which it forms more than 3%. It is an essential constituent of leaves, bones, teeth, and shells. Never found in nature uncombined, it occurs abundantly as limestone, gypsum, and fluorite. Apatite is the fluorophosphate or chlorophosphate of calcium.

The metal has a silvery color, is rather hard, and is prepared by electrolysis of fused chloride and calcium fluoride (to lower the melting point).

Chemically it is one of the alkaline earth elements; it readily forms a white coating of nitride in air, reacts with water, burns with a yellow-red flame.

Its natural and prepared compounds are widely used. Quicklime (CaO), which is made by heating limestone that is changed into slaked lime by carefully adding water, is the great base of chemical refinery with countless uses.

When mixed with sand, it hardens mortar and plaster by taking up carbon dioxide from the air. Calcium from limestone is an important element in Portland cement.

Solubility of the carbonate in water containing carbon dioxide is high, which causes the formation of caves with stalactites and stalagmites and is responsible for hardness in water. Other important compounds are the carbide, chloride, cyanamide, hypochlorite, nitrate, and sulfide.

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As friends, ENFPs are cheerful and supportive, always sharing and developing ideas, and staying open-minded, taking in others’ thoughts and feelings. This warmth and sincerity makes people with the ENFP personality type masters of drawing people out of their shells, and as a result they tend to have a huge circle of friends.

More outgoing types will naturally gravitate towards them, but ENFPs will also go to great lengths and be surprisingly persistent in their efforts to get to know more reserved personalities. Their ability to tune into others and speak their language with that characteristic infectious enthusiasm helps them in this endeavor, and the allure of mystery that reserved types, especially Introverted Intuitives, bring to the table will keep ENFPs intrigued for years. These personality types may never be able to reciprocate the breadth of human interest that ENFPs present, but they do appreciate ENFPs’ efforts.

But ENFPs’ interest in others can be a double-edged sword – this pure idealism comes with certain expectations, and too often ENFPs hold their friends in an unrealistic light, expecting them to keep up with the constant flow of ideas and experiences that they consider integral to life. ENFPs put their whole hearts into their friendships, and it can come as a shock for them to find that their friends aren’t the flawless Titans that they believed them to be. Whether it’s simple social fatigue or a focus on the physical and the practical instead of the mystical, people with the ENFP personality type can find themselves disappointed by what they see as a lack of substance beneath the surface.

ENFPs tend to get deeply involved in others’ lives, going to great lengths and efforts to be the selfless, caring and supportive people they are, and all the while forget to take care of themselves. Both in terms of basic needs like financial stability and rest, as well as more emotional needs like mutual understanding and reciprocation, ENFP personalities tend to give much more of themselves than most are even capable of giving back. This sort of imbalance isn’t sustainable, as (seemingly) one-sided generosity often leads to criticism and resentment on both sides.

Luckily, ENFPs are open-minded and sincere enough in their friendships, and connect with and understand even their acquaintances well enough, that they recognize that not everyone expresses themselves in the same ways, and that that’s okay. Their sensitivity may make it too challenging to play with more critical and argumentative personalities, such as strongly expressed Thinking (T) and Judging (J) types, but they do appreciate, even cherish, the company of most anyone who appreciates theirs, and the adventures and experiences they have together are the stuff a good life is made of.

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CLEVELAND -- James Schamus makes his directing debut with "Indignation," but he's hardly a newbie in the independent film world.

As a screenwriter and producer, he has collaborated since 1992 with director Ang Lee on films as varied as "Eat Drink Man Woman," "Brokeback Mountain" and "Crouching Tiger, Hidden Dragon." As the longtime head of Focus Features, he championed the likes of Sofia Coppola, Todd Haynes and Mira Nair.

All of that experience informs his work writing and directing "Indignation," a finely calibrated, if a bit deliberate, adaptation of Philip Roth's 2008 coming-of-age novel.

It is 1951, and Marcus Messner (Logan Lerman) -- one of Roth's many literary alter egos -- is fleeing both the war in Korea and his overbearing Jewish parents in Newark, New Jersey, by heading to Ohio for college.

"Ohio?" says a neighbor, in a tone that suggests Marcus is planning to study with the pope himself at the Vatican. "How will you keep kosher?"

That's the least of Marcus's concerns once he arrives at Winesburg College (Sherwood Anderson reference intended) and discovers that he's one of just 80 Jews on a campus of 1,400, and that his presence will be required at weekly chapel for prayers and Christian teachings.

Before he leaves, his anxious father (Danny Burstein) is already in mourning, wailing, "If anything should happen to you! It's about the tiniest mistake that can happen to you!"

Which states, in blinking neon, the core theme of Roth's novel: Death is going to happen to you, like it or not, and you will make the decisions - or mistakes -- that cause it.

What mistakes does Marcus make at Winesburg? First, he falls for Olivia Hutton (Sarah Gadon), a dazzling, sexually liberated shiksa who turns out to be a deeply troubled girl. Then, he mixes it up in two extended arguments with the pompous Dean Caudwell (Tracy Letts), who admires Marcus's intellectual acumen but wants him to conform to the stultifying culture of Winesburg.

The first of these debates forms the centerpiece of "Indignation," a gambit that works far better in print than on screen. Though both actors handle the heated argument with agility and even a touch of wry humor, it's still 15 minutes of two people talking in an office, and it grows tiresome.

At a crisis point, Marcus's mother (Linda Emond) arrives from Newark on a rescue mission. In one of Roth's signature ironies, though, her meddling is that "tiniest mistake" in a chain of mistakes that lead to disaster.